📄️ Overview
Since developing smart contract-based applications on UTXO-model chains is a vastly different experience compared to other account-model chains like Ethereum, certain fundamental principles should be established whenever you intend to build a CAT protocol-based application.
📄️ CAT20
CAT20 standard is a part of the Covenant Attested Token (CAT) protocol which supports fungible tokens. As you all know, CAT is a UTXO-based token protocol that is validated by miners directly and uses smart contracts, specifically covenants, to manage token mints and transfers. It is solely enforced by Bitcoin Script at Layer 1 and has several benefits compared with all the existing token protocols on Bitcoin.
📄️ CAT721
CAT721 standard is a part of the Covenant Attested Token (CAT) protocol, which supports non-fungible tokens. Unlike CAT20 tokens, CAT721 tokens cannot be divided into smaller units. Each token is unique and non-interchangeable, i.e., non-fungible. Each NFT stores full data on-chain immutably using Bitcoin transactions.